Write once disc, disc drive therefor, and method of managing disc defect considering compatibility with rewritable disc drive

ABSTRACT

A write once disc, a disc drive therefor, and a method of managing disc defects on the write once disc using the disc drive in consideration of the compatibility of the write once disc with a rewritable disc drive, the write once disc includes a single record layer disc in which a lead-in area, a data area, and a lead-out area are sequentially formed and a first spare area and a second spare area are sequentially formed in the data area. The write once disc includes a defect management area (DMA) formed in at least one of the lead-in area and the lead-out area; a first temporary defect management area (TDMA) formed in at least one of the lead-in area and the lead-out area; and a second TDMA formed between the first spare area and a user data area or between the user data area and the second spare area.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.10/797,105 filed Mar. 11, 2004, now U.S. Pat. No. 7,327,655 and alsoclaims the priority of Korean Patent Application No. 2003-23518 filed onApr. 14, 2003, in the Korean Intellectual Property Office, thedisclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to disc defect management for a write oncedisc, and more particularly, to a write once disc, a disc drivetherefor, and a method of performing disc defect management inconsideration of the compatibility with a rewritable disc drive.

2. Description of the Related Art

Disc defect management is the process of rewriting data stored in a userdata area of a disc in which a defect exists to a new portion of thedisc's data area, thereby compensating for data loss caused by thedefect. In general, disc defect management is performed using linearreplacement or slipping replacement methods. In the linear replacementmethod, a user data area in which a defect exists is replaced with aspare data area having no defects. In the slipping replacement method, auser data area with the defect is slipped and the next user data areahaving no defects is used.

Both linear replacement and slipping replacement methods are, however,applicable only to discs such as a DVD-RAM/RW, on which data can berepeatedly recorded and recording can be performed using a random accessmethod. In other words, the conventional linear replacement and slippingreplacement methods cannot be applied to write once discs on whichrecording is allowed only once. In general, the presence of defects in adisc is detected by recording data on the disc and confirming whether ornot data has been recorded correctly on the disc. However, once the datais recorded on a write once disc, it is impossible to overwrite new dataand manage defects therein.

After the development of a CD-R and a DVD-R, a high-density write oncedisc with a recording capacity of several dozen GBs has been introduced.This type of disc can be used as a backup disc since it is not expensiveand allows random access that enables fast reading operations. However,disc defect management is not available for write once discs. Therefore,a backup operation may be discontinued when a defective area, i.e., anarea where a defect exists, is detected during the backup operation. Ingeneral, the backup operation is performed when a system is notfrequently used, e.g., at night when a system manager does not operatethe system. In this case, it is more likely that the backup operationwill be discontinued because a defective area of a write once disc isdetected.

Meanwhile, when additional data will not be recorded on a recordabledisc, i.e., when only data reproduction will be allowed, write protectinformation is recorded on the disc to prevent the data recorded on thedisc from being mistakenly erased. However, once the write protectinformation is recorded, recording is not further allowed, and, thus,possible disc defects cannot be managed. Because recording is notallowed in a data area of the disc after recording of the write protectinformation, disc defect management cannot be performed.

Conventionally, location information regarding disc areas for discdefect management has been specified in the specifications and a discdrive designer designs a disc drive based on the specifications.Accordingly, if a new disc area is further added to the existing discareas, a conventional disc drive cannot recognize the presence of thenew disc area and satisfactorily perform disc defect management.

SUMMARY OF THE INVENTION

The present invention provides a write once disc, and a disc defectmanagement method and disc drive capable of managing disc defects evenwhen a defect is detected during a recording operation, thereby allowingthe recording operation to be performed without interruption.

The present invention also provides a write once disc with a temporarydefect management area(s) and a method and apparatus managing discdefects in consideration of the compatibility with a rewritable discdrive,

According to an aspect of the present invention, there is provided amethod of managing disc defects occurring on a write once disc that is asingle record layer disc in which a lead-in area, a data area, and alead-out area are sequentially formed and a first spare area and asecond spare area are formed at both ends of the data area, the methodincluding allocating a first temporary defect management area (TDMA) toat least one of the lead-in area and the lead-out area; allocating asecond TDMA between the first spare area and a user data area or betweenthe user data area and the second spare area; and performing disc defectmanagement using the first and second TDMAs.

According to another aspect of the present invention, there is provideda method of managing disc defects occurring on a write once disc that isa double record layer disc including a first record layer in which alead-in area, a data area, and an outer area are formed along arecording path and a first spare area and a second spare area are formedat the both ends of the data area; and a second record layer in which anouter area, a data area, and a lead-out area are formed along arecording path and a third spare area and a fourth spare area are formedat the both ends of the data area, the method including allocating afirst temporary defect management area (TDMA) to at least one of thelead-in area, the lead-out area, and the outer area; allocating a secondTDMA between the first spare area and a user data area and/or betweenthe fourth spare area and the user data area; and performing disc defectmanagement using the first and second TDMAs.

According to yet another aspect of the present invention, there isprovided a method of managing disc defects occurring on a write oncedisc, the method including updating a second TDMA of a data area of thewrite once disc whenever data is recorded in the data area in apredetermined recording period; updating a first TDMA formed in at leastone of a lead-in area, a lead-out area, and an outer area of the writeonce disc whenever data is recorded in a data area of the write oncedisc in another predetermined recording period; and recording temporarymanagement information, which is most recently updated and recorded inthe first or second TDMA, in a defect management area (DMA) formed in atleast one of the lead-in area, the lead-out area, and the outer area.

According to still another aspect of the present invention, there isprovided a disc drive including a pickup that records data on or readsdata from a write once disc; and a controller that controls the pickupto allocate a first TDMA to at least one of a lead-in area and alead-out area of the write once disc, allocate a second TDMA between afirst spare area and a user data area or between the user data area anda second spare area, and perform disc defect management on the writeonce disc using the allocated first and second TDMAs. The write oncedisc is a single record layer disc in which the lead-in area, a dataarea, and the lead-out area are sequentially formed and the first andsecond spare areas are formed at both ends of the data area.

According to still another aspect of the present invention, there isprovided a disc drive including a pickup that records data on or readsdata from a write once disc; and a controller that controls the pickupto allocate a first TDMA to at least one of a lead-in area, a lead-outarea, and an outer area of the write once disc, allocate a second TDMAbetween a first spare area and a user data area and/or between a fourthspare area and the user data area, and perform disc defect management onthe write once disc using the allocated first and second TDMAs. Thewrite once disc is a double record layer disc including a first recordlayer in which the lead-in area, a data area, and the outer area areformed along a recording path, and the first spare area and a secondspare area are formed at both ends of the data area; and including asecond record layer in which an outer area, a data area, and a lead-outarea are formed along a recording path, and a third spare area and thefourth spare area are formed at both ends of the data area.

According to still another aspect of the present invention, there isprovided a disc drive including a pickup that records data on or readsdata from a write once disc; and a controller that controls the pickupto update a second TDMA formed in a user data area of the write oncedisc whenever data is recorded in the user data area in a predeterminedrecording period; update a first TDMA formed in at least one of alead-in area, a lead-out area, and an outer area of the write once discwhenever data is recorded in the user data area in another predeterminedrecording period; and record temporary management information, which isrecently updated and recorded in the first or second TDMA, in a DMAformed in at least one of the lead-in area, the lead-out area, and theouter area.

According to still another aspect of the present invention, there isprovided a write once disc that is a single record layer disc in which alead-in area, a data area, and a lead-out area are sequentially formedand a first spare area and a second spare area are sequentially formedin the data area, the write once disc comprising a DMA formed in atleast one of the lead-in area and the lead-out area; a first TDMA formedin at least one of the lead-in area and the lead-out area; and a secondTDMA formed between the first spare area and a user data area or betweenthe user data area and the second spare area.

According to still another aspect of the present invention, there isprovided a write once disc that is a double record layer disc includinga first record layer in which a lead-in area, a data area, and an outerarea are sequentially formed along a recording path and a first sparearea and a second spare area are formed at both ends of the data area,and including a second record layer in which an outer area, a data area,and a lead-out area are sequentially formed along a recording path and athird spare area and a fourth spare area are formed at both ends of thedata area, the write once disc comprising a DMA formed in at least oneof the lead-in area, the lead-out area, and the outer area; a first TDMAformed in at least one of the lead-in area, the lead-out area, and theouter area; and a second TDMA formed between the first spare area and auser data area and/or between the fourth spare area and the user dataarea.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe embodiments, taken in conjunction with the accompanying drawings ofwhich:

FIG. 1 is a block diagram of a recording and/or reproducing apparatusaccording to an embodiment of the present invention;

FIG. 2 is a block diagram of a disc drive that is another embodiment ofthe recording and/or reproducing apparatus of FIG. 1;

FIG. 3A illustrates a data structure of a disc with a single recordlayer, to which a temporary defect management area (TDMA) will beadditionally allocated, according to an embodiment of the presentinvention;

FIG. 3B illustrates a data structure of a lead-in area of the disc ofFIG. 3A, according to an embodiment of the present invention;

FIGS. 4A and 4B illustrate data structures of the disc of FIG. 3Afurther including an additional TDMA, according to embodiments of thepresent invention;

FIG. 5 illustrates data structures of a disc that are not compatiblewith a rewritable disc drive;

FIG. 6A illustrates a data structure of a disc with two record layers,to which a temporary defect management area (TDMA) will be additionallyallocated, according to an embodiment of the present invention;

FIG. 6B illustrates a data structure of a lead-in/lead-out area of thedisc of FIG. 6A, according to an embodiment of the present invention;

FIG. 7 illustrates a data structure of the disc of FIG. 6A furtherincluding an additional TDMA, according to an embodiment of the presentinvention;

FIGS. 8A through 8D illustrate data structures of a TDMA according toembodiments of the present invention;

FIG. 9 illustrates diagrams explaining recording of data in a user dataarea A and a spare area B, according to an embodiment of the presentinvention;

FIG. 10 illustrates data structures of temporary defect information TDFL#1 and TDFL #2 according to embodiments of the present invention;

FIG. 11 illustrates a data structure of information regarding defect #i;

FIG. 12 is a flowchart illustrating a disc defect management methodaccording to an embodiment of the present invention; and

FIG. 13 is a flowchart illustrating a disc defect management methodaccording to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below to explain the presentinvention by referring to the figures.

FIG. 1 is a block diagram of a recording and/or reproducing apparatusaccording to an embodiment of the present invention. Referring to FIG.1, the recording and/or reproducing apparatus includes arecording/reading unit 1, a controller 2, and a memory 3. Therecording/reading unit 1 records data on a disc 100, which is aninformation storage medium according to an embodiment of the presentinvention, and reads back the data from the disc 100 to verify theaccuracy of the recorded data. The controller 2 performs disc defectmanagement according to the present invention. More specifically, thecontroller 2 further allocates two temporary defect management areas(TDMAs) to the disc 100 according to a user input or in a predeterminedmanner, and performs disc defect management on the disc 100 using thetwo TDMAs.

In this embodiment, the controller 2 uses a verify-after-write method inwhich data is recorded on the disc 100 in predetermined units of dataand the accuracy of the recorded data is verified to detect if an areaof the disc 100 has a defect. In other words, the controller 2 recordsuser data on the disc 100 in units of recording operations and verifiesthe recorded user data to detect an area of the disc 100 in which adefect exists. Thereafter, the controller 2 creates defect informationwhich indicates the position of the area with the defect and stores thecreated defect information in the memory 3. When the stored defectinformation reaches a predetermined amount, the controller 2 records thestored defect information as temporary defect information in the twoTDMAs of the disc 100. In this disclosure, information recorded in aTDMA will be referred to as temporary management informationcorresponding to management information, managing disc defects, which isrecorded in a defect management area (DMA).

In this embodiment, whenever the verify-after-write method is completedat least once, the controller 2 reads the defect information from thememory 3, provides the defect information to the recording/reading unit1, and controls the recording/reading unit 1 to record the defectinformation as temporary management information in the TDMAs. Further,when a user presses the eject button (not shown) of the recordingapparatus in order to remove the disc 100 after the recording of data,the controller 2 expects the recording operation to be completed. Next,the controller 2 reads the defect information from the memory 3,provides the defect information to the recording/reading unit 1, andcontrols the recording/reading unit 1 to record the defect informationin the TDMAs of the disc 100.

When the recording of data is completed, i.e., additional data will notbe recorded on the disc 100 (the disc 100 needs to be finalized), thecontroller 2 controls the recording/reading unit 1 to rewrite therecorded temporary management information to the DMA of the disc 100.

In general, a size of a DMA allocated to a rewritable disc is not large.If a write once disc includes a DMA with the same size and position asthat of the rewritable disc in consideration of only the compatibilitywith a rewritable disc drive, data may not be further recorded in theDMA before a data area of the write once disc is fully recorded. In thiscase, disc defect management cannot be further performed. For thisreason, according to the present invention, the TDMAs are additionallyformed in a write once disc and lastly recorded information is recordedin the DMA for disc finalization, thus enabling the rewritable discdrive to accurately perceive areas allocated to the write once disc.That is, a write once disc according to the present invention iscompatible with the rewritable disc drive.

FIG. 2 is a block diagram of a disc drive that is an embodiment of therecording and/or reproducing apparatus of FIG. 1. The disc drive of FIG.2 includes a pickup 10 acting as the recording/reading unit 1 of FIG. 1.A disc 100 is loaded onto the pickup 10. Also, the disc drive includes aPC interface (I/F) 21, a digital signal processor (DSP) 22, aradio-frequency (RF) amplifier 23, a servo 24, and a system controller25 which correspond to the controller 2 of FIG. 1. The system controller25 also acts as the memory 3 of FIG. 1.

During a write operation, the PC I/F 21 receives data to be recorded anda write command from a host (not shown). The system controller 25performs disc initialization prior to data recording. The DSP 22 addsadditional data such as parity into the data transmitted from the PC I/F21, performs error correction coding (ECC) on the data, and modulatesthe ECC encoded data using a predetermined method. The RF amplifier 23converts data output from the DSP 22 into an RF signal. The pickup 10records the RF signal output from the RF amplifier 23 on the disc 100.The servo 24 receives a servo control command from the system controller25 and performs a servo control on the pickup 10. Also, the systemcontroller 25 instructs the recorded data to be read by the pickup 10 orpredetermined information such as temporary management information to berecorded, so as to perform disc defect management according to thepresent invention.

During a read operation, the PC I/F 21 receives a read command from thehost and the system controller 25 performs data reading discinitialization. The pickup 10 irradiates a laser beam onto the disc 100and receives a laser beam reflected from the disc 100, converts thelaser beam into an optical signal, and outputs the optical signal. TheRF amplifier 23 converts the optical signal output from the pickup 10into an RF signal, provides data obtained by modulating the RF signal tothe DSP 22, and provides a servo control signal obtained from the RFsignal to the servo 24. The DSP 22 demodulates the modulated data,performs ECC on the demodulated data, and outputs the error correctioncoded data. The servo 24 receives the servo control signal from the RFamplifier 23 and the servo control command from the system controller 25and performs servo control on the pickup 10. The PC I/F 21 transmits theerror correction coded data from the DSP 22 to the host. Also, duringthe read operation, the system controller 25 may instruct informationfor disc defect management to be read by the pickup 10, that is, thesystem controller manages the overall system during a read/writeoperation.

FIG. 3A illustrates a data structure of the disc 100 of FIG. 1 having asingle record layer L0 to which a temporary defect management area(TDMA) will be additionally allocated, according to an embodiment of thepresent invention. FIG. 3B illustrates a data structure of a lead-inarea of the disc 100 of FIG. 3A, according to an embodiment of thepresent invention.

Referring to FIG. 3A, the disc 100 includes a lead-in area, a data area,and a lead-out area. The lead-in area and the lead-out area are locatedin an inner part and an outer part of the disc 100, respectively. Thedata area is present between the lead-in area and the lead-out area andis divided into a first spare area, a user data area, and a second sparearea starting from the inner part of the disc 100.

The user data area is an area where user data is recorded. The first andsecond spare areas are replacement areas for a user data area having adefect, serving to compensate for loss in the recording area due to thedefect. On the assumption that defects may occur within the disc 100,[it is preferable that] the spare area is about 5% of the entire datacapacity of the disc 100, so that a greater amount of data can berecorded on the disc 100.

Referring to FIG. 3B, the lead-in area of FIG. 3A includes a defectmanagement area (DMA) and a first temporary defect management area(TDMA). The first TDMA is located within a range that does not changethe positions of the lead-in area and the lead-out area defined withrespect to a write once disc or rewritable disc. Unlike a rewritabledisc, a write once disc further requires a TDMA to perform disc defectmanagement using the disc drive of FIG. 2. As previously mentioned, incontrast to the rewritable disc, once data is recorded on the write oncedisc, it is impossible to overwrite new data. Thus, the disc 100, whichis the write once disc, requires a new area, such as the TDMA, forrecording updated information. A size of the new area is spacious enoughto allow update information to be recorded therein a plurality of numberof times. Meanwhile, like the rewritable disc, the lead-in area of thewrite once disc includes a test area recording condition test and adrive information area recording information regarding a disc drive. TheDMA and/or TDMA may be formed in the lead-out area.

Like the rewritable disc on which disc defect management can beperformed, the DMA of the disc 100 includes information regarding a sizeof a first spare area, information regarding a starting position of auser data area, information regarding an ending position of the userdata area, and information regarding a size of a second spare area.Accordingly, the disc drive of FIG. 2 reads this information to detectthe starting and ending positions of the user data area and recognizesthe first and second spare areas based on the starting and endingpositions and the information regarding their sizes.

FIGS. 4A and 4B illustrate data structures of the disc of FIG. 3Afurther including a second TDMA, according to embodiments of the presentinvention.

Referring to FIG. 4A, the second TDMA is allocated between a first sparearea and a user data area of the disc 100 at a beginning of a write/readoperation, according to the user input. Starting and ending positions ofthe data area are set as shown with respect to FIG. 3B and maintained.

Temporary management information is recorded in a first TDMA and thesecond TDMA. The temporary management information includes temporarydefect information and management information managing the temporarydefect information. Further, in this embodiment, a space bit map isrecorded in the first and second TDMAs.

The first TDMA is updated in recording operation units, and the secondTDMA is updated whenever information is recorded in a predeterminednumber of cluster units or whenever the verify-after-write method isperformed at least once. Thus, the second TDMA must be spacious becausethe second TDMA is updated more often than the first TDMA. For thisreason, it is preferable that the first TDMA is formed in the lead-inarea or the lead-out area and the second TDMA is allocated to the dataarea which has a larger storage area.

The second TDMA is not allocated when a user does not desire to performdisc defect management using the disc drive, or when the user does notwant to allocate the second TDMA although he or she desires to performdisc defect management using the disc drive. In other words, the secondTDMA is allocated to the data area at a beginning of the write/readoperation only when the user desires disc defect management to beperformed on the disc 100 using the disc drive and the second TDMA.

Referring to FIG. 4B, when the user desires to allocate a second TDMA,the second TDMA is allocated between a user data area and a second sparearea of a data area of the disc 100 at a beginning of a write/readoperation. Similarly, the second TDMA is not allocated when the userdoes not desire to perform disc defect management using the disc drive,or when the user does not want to allocate the second TDMA although theuser desires to perform disc defect management using the disc drive.That is, the second TDMA is allocated to the data area at a beginning ofthe write/read operation only when the user desires disc defectmanagement to be performed on the disc 100 using the disc drive and thesecond TDMA.

A data structure of each area of the disc 100 of FIG. 4B is the same asthat of each area of the disc 100 of FIG. 4A. Therefore, a detaileddescription thereof will not be repeated here.

The second TDMA shown in FIG. 4A or 4B is helpful for the followingreasons. The first TDMA is updated in recording operation units and thedisc drive temporarily stores updated temporary management informationduring a recording operation. If a power failure occurs when the discdrive is in a stand by mode in another recording operation, thetemporarily stored management information will be lost, causing aproblem to occur when the disc 100 is used later. In contrast, thesecond TDMA is updated whenever the verify-after-write method isaccomplished. Therefore, it is possible to prevent data loss, that is,disc damage, even when a power failure occurs during a recordingoperation of the disc drive. Next, the verify-after-write method isperformed a predetermined number of times during a recording operation.The predetermined number of times is an integer. Thus, if the first TDMAis updated whenever the verify-after-write method is performed, the mostrecent information is recorded in both the first and second TDMAs afterthe recording operation is completed, thereby increasing the robustnessof information. Accordingly, inclusion of the second TDMA on the disc100 solves a problem caused by a power failure occurring in a writestand-by mode and increases the robustness of information.

FIG. 5 illustrates data structures of a write once disc that are notcompatible with a rewritable disc drive. Referring to FIG. 5, case 1shows a data structure of a write once disc such as that shown in FIG.3A. If the write once disc of case 1 is loaded into the rewritable discdrive, the rewritable disc drive recognizes first and second spare areasbased on the information regarding starting and ending positions of auser data area as described with reference to FIG. 3, the informationbeing recorded in a DMA. Also, because the position of each area shownin case 1 is equivalent to that of each area of FIG. 3A, the rewritabledisc drive can appropriately perform a read command from a host (notshown) by reading replacements, for data stored in a portion of the userdata area in which a defect exists, which are recorded in the first andsecond spare areas as a result of disc defect management. Further, thestarting and ending positions of the user data area is specified in theDMA, and thus an improper area is prevented from being mistakenlyrecognized during the read operation.

However, if the second TDMA is allocated to a write once disc as shownin cases 2 through 4, that is, the second TDMA is allocated to a portionof a data area, other than those shown in FIGS. 4A and 4B, therewritable disc drive may not reproduce information stored in the writeonce disc for the following reasons.

The rewritable disc drive recognizes the user data area and the firstand second spare areas, based on the starting and ending positions ofthe data area defined in the specifications and the information recordedin the DMA of FIG. 3B.

More specifically, the rewritable disc drive recognizes a zone, whichranges from a start of the data area and has a size as defined in theinformation regarding a size of the first spare area, as the first sparearea. Also, the rewritable disc drive recognizes a zone, which rangesfrom an end of the data area and has a size as defined in theinformation regarding a size of the second spare area, as the secondspare area. Further, the rewritable disc drive recognizes a zone, whichranges from the starting position of the user data area to the endingposition thereof, as the user data area.

Accordingly, when a write once disc with a data structure shown in cases2 through 4 is loaded into the rewritable disc drive, the rewritabledisc drive will mistakenly recognize the various areas. For instance,the rewritable disc drive cannot detect first and second spare areasfrom the write once disc shown in cases 2 and 3, and cannot detect auser data area from the write once disc shown in case 4. Accordingly,the second TDMA is required to be allocated as shown in FIG. 4A or 4B sothat the rewritable disc drive can recognize each area of a write oncedisc.

FIG. 6A illustrates a data structure of the disc 100, having two recordlayers L0 and L1, to which a temporary defect management area (TDMA)will be additionally allocated, according to an embodiment of thepresent invention. FIG. 6B illustrates a data structure of alead-in/lead-out area of the disc 100 of FIG. 6A, according to anembodiment of the present invention.

Referring to FIG. 6A, a lead-in area, a data area, and an outer area aresequentially formed from the inner part of the first record layer L0 toits outer part. Also, an outer area, a data area, and a lead-out areaare sequentially formed from the outer part of the second record layerL1 to its inner part. Unlike the single record layer disc of FIG. 3A,the lead-out area is present in the inner part of the disc 100 of FIG.6A. That is, the disc 100 of FIG. 6A has an opposite track path (OTP) inwhich data is recorded starting from the lead-in area of the firstrecord layer L0 toward its outer area and continuing from the outer areaof the second record layer L1 to its lead-out area. Two spare areas areallotted to each of the record layers L0 and L1. That is, a first sparearea and a second spare area are formed in the first record layer L0 anda third spare area and a fourth spare area are formed in the secondrecord layer L1.

Referring to FIG. 6B, the lead-in area (and/or the lead-out area)includes a DMA and a first TDMA. The first TDMA is located within arange that does not change the positions of the lead-in area and thelead-out area defined with respect to a write once disc or rewritabledisc. The reason why the write once disc according to the presentinvention requires the first TDMA is the same as described withreference to FIG. 3B. The DMA and/or the first TDMA may be formed in theouter area.

As in a rewritable disc on which disc defect management can beperformed, information regarding a size of the first spare area,information regarding a starting position of a user data area,information regarding an ending position of the user data area,information regarding a sum of sizes of the second and third spareareas, and information regarding a size of the fourth spare area havebeen recorded in the DMA of the disc 100 with two record layers. Becausea disc drive has already obtained information regarding starting andending positions of the data area, the disc drive reads the informationstored in the DMA to recognize the starting and ending positions of theuser data area and the first through fourth spare areas. Here, thesecond and third spare areas have the same sizes.

FIG. 7 illustrates a data structure of the disc 100 of FIG. 6A furtherincluding a second TDMA, according to an embodiment of the presentinvention. Referring to FIG. 7, the second TDMA is formed between afirst spare area and a user data area in the first record layer L0 ofthe disc 100 and formed between a user data area and a fourth spare areain the second record layer L1. Starting and ending positions of eachrecord layer are as shown in FIG. 6A. Accordingly, a rewritable discdrive, for a rewritable disc with two record layers, is capable ofaccurately recognizing each area of the disc 100 that is a write oncedisc with two record layers. However, when the second TDMA is allocatedto a portion of a data area, other than those shown in FIG. 7, therewritable disc drive cannot recognize each area of the disc 100 (fordetails, see the description regarding FIGS. 4A and 4B).

Referring to FIG. 6A, the disc 100 includes a DMA in at least one of thelead-in area, the lead-out area, and the outer area, and includes a TDMAin at least one of the lead-in area and the lead-out area.

In general, information relating to managing disc defects in the disc100 is recorded in the DMA. Such information includes the structure ofthe disc 100 for disc defect management, the recording position ofdefect information, whether defect management is performed or not, andthe position and size of a spare area. Because the disc 100 is a writeonce disc, new data is recorded after previously recorded data when theabove information changes.

In general, when a disc is loaded into a recording/reproducingapparatus, the apparatus reads data from a lead-in area and a lead-outarea of the disc to determine how to manage the disc and record data onor read data from the disc. However, if the amount of data recorded inthe lead-in area and/or the lead-out area increases, a longer time isspent on preparing the recording or reproducing of data after theloading of the disc. To solve this and/or other problems, the presentinvention uses temporary defect management information and temporarydefect information that are to be recorded in a TDMA allotted to thelead-in area and/or the lead-out area.

Hereinafter, disc defect management according to an embodiment of thepresent invention will be described with respect to the disc 100, i.e.,a write once disc, such as that shown in FIG. 4A, 4B, or 7, the disc 100including a second TDMA. The present applicants have filed other Koreanpatent applications regarding disc defect management, e.g., Koreanpatent application No. 2002-61897 filed on Oct. 10, 2002. Details fordisc defect management are well described in these applications.

In this embodiment, disc defect management is performed using the linearreplacement method. Temporary defect information is recorded as a resultof disc defect management in a first TDMA through a fourth TDMA andincludes temporary defect information and temporary defect managementinformation. The temporary defect information specifies a location of aportion, i.e., a defective portion, of the disc 100 in which a defectoccurs and a location of a replacement for data stored in the defectiveportion. The temporary defect management information is used to managethe temporary defect information and specifies a recording position ofthe temporary defect information.

In this embodiment, the temporary defect information and temporarydefect management information recorded in the second TDMA or the fourthTDMA are recorded periodically, i.e., they are recorded whenever data isrecorded in a user data area in a number of cluster units or theverify-after-write method is performed at least once. The temporarydefect information and temporary defect management information recordedin the first TDMA or the third TDMA are recorded whenever a recordingoperation ends. When temporary defect information and temporary defectmanagement information are newly recorded in the first or second TDMA,the first or second TDMA is considered as being updated.

Lastly recorded temporary defect information and temporary defectmanagement information, i.e., most recently updated and recordedtemporary defect information and temporary defect managementinformation, are recorded in the DMA for disc finalization for thefollowing reason. In the case that additional data will not be recordedon the disc 100, i.e., the disc 100 needs to be finalized, the temporarydefect management information and temporary defect information, whichhave been updated several times, are again recorded in the DMA.Accordingly, the recording/reproducing apparatus can fast read defectmanagement information from the disc 100 just by reading temporarydefect management information and temporary defect information that havebeen recorded last in the DMA. Further, recording of the temporarydefect information and temporary defect management information in theDMA increases the reliability of information.

FIGS. 8A through 8D illustrate data structures of a TDMA according toembodiments of the present invention. The TDMA of FIG. 8A is logicallydivided into a temporary defect information area and a temporary defectmanagement information area. In the temporary defect information area,temporary defect information TDFL #1, TDFL #2, TDFL #3, . . . aresequentially recorded starting from the start of this area toward itsend. In the temporary defect management information area, temporarydefect management information TDDS #1, TDDS #2, TDDS #3, . . . aresequentially recorded starting from the start of this area. Thetemporary defect management information TDDS #1, TDDS #2, and TDDS #3corresponds to the temporary defect information TDFL #1, TDFL #2, andTDFL #3, respectively.

Referring to FIG. 8B, compared to FIG. 8A, a DMA is also logicallydivided into a temporary defect information area and a temporary defectmanagement information area, but the sequences of recording informationare not the same. More specifically, in the temporary defect informationarea, temporary defect information TDFL #1, TDFL #2, TDFL #3, . . . aresequentially recorded starting from the end of this area toward itsstart. In the temporary defect management information area, temporarydefect management information TDDS #1, TDDS #2, TDDS #3, . . . aresequentially recorded starting from the end of this area. The temporarydefect management information TDDS #1, TDDS #2, and TDDS #3 correspondsto the temporary defect information TDFL #1, TDFL #2, and TDFL #3,respectively.

Referring to FIG. 8C, corresponding temporary defect information andtemporary defect management information are recorded as pairs ofinformation in a TDMA. More specifically, temporary managementinformation TDMA #1, TDMA #2, are sequentially recorded starting fromthe start of the TDMA. The temporary management information TDMA #1contains a pair of corresponding temporary defect information TDFL #1and temporary defect management information TDDS #1, and temporarymanagement information TDMA #2 contains a pair of correspondingtemporary defect information TDFL #2 and temporary defect managementinformation TDDS #2.

Referring to FIG. 8D, compared to the TDMA of FIG. 8C, correspondingtemporary defect information and temporary defect management informationare recorded as pairs of information in a TDMA, but the sequence ofrecording the information is not the same. More specifically, in theTDMA, temporary management information TDMA #1, TDMA #2, . . . aresequentially recorded starting from the end of the TDMA. The temporarymanagement information TDMA #1 contains a pair of correspondingtemporary defect management information TDDS #1 and temporary defectinformation TDFL #1, and the temporary management information TDMA #2contains a pair of corresponding temporary defect management informationTDDS #2 and temporary defect information TDFL #2.

FIG. 9 is a reference diagram illustrating in detail recording of datain a user data area A and a spare area B, according to an embodiment ofthe present invention. Referring to FIG. 9, A denotes a user data areaand B denotes a spare area in which Physical Sector Numbers (PSNs) aresequentially allocated to a plurality of sectors (not shown). Ingeneral, each Logical Sector Number (LSN) corresponds to at least onePSN. However, because LSNs are allocated to non-defective areas,including replacements recorded in the spare area, the correspondencebetween the PSNs and the LSNs is not maintained when a disc has adefective area, even if the size of a physical sector is the same asthat of a logical sector.

In the data area A, sections {circle around (1)} through {circle around(7)} denote predetermined units of data in which the verify-after-writemethod is performed. A disc drive records user data in section {circlearound (1)}, returns to the start of section {circle around (1)}, andchecks if the user data is appropriately recorded or a defect exists insection {circle around (1)}. If a defect is detected in a portion ofsection {circle around (1)}, the portion is designated as defect #1. Theuser data recorded in defect #1 is also recorded on a portion of thespare area B. Here, the portion of the spare area B is referred to asreplacement #1.

If a second TDMA is updated whenever the verify-after-write method iscompleted, the disc drive records information regarding defect #1 andinformation regarding replacement #1 as temporary defect informationTDFL #1 in the second TDMA. Also, management information to manage thetemporary defect information TDFL #1 is recorded as temporary defectmanagement information TDDS #1 in the second TDMA.

Next, the disc drive records user data in section {circle around (2)},returns to the start of section {circle around (2)}, and checks whetherthe user data is properly recorded or a defect exists in section {circlearound (2)}. If a defect is detected in a portion of section {circlearound (2)}, the portion is designated as defect #2. Likewise,replacement #2 corresponding to defect #2 is formed in the spare area B.Information regarding defect #2 and information regarding replacement #2are recorded as temporary defect information TDFL #2 in the second TDMA.Also, management information to manage the temporary defect informationTDFL #2 is recorded as temporary defect management information TDDS #2in the second TDMA.

Further, defect #3 and replacement #3 are designated in section {circlearound (3)} of the user data area A and the spare area B, respectively.Similarly, the second TDMA is updated. In section {circle around (4)}, adefect does not occur and a defective area is not designated. The discdrive records information regarding defect #1, #2, and #3 occurring insections {circle around (1)} through {circle around (4)} as temporarydefect information TDFL #1 in a first TDMA, when recording operation #1is expected to end, after the recording and verifying of data to section{circle around (4)}, i.e., when a user presses the eject button of therecording and/or reproducing apparatus or recording of user dataallocated in a recording operation is completed. Also, managementinformation to manage the temporary defect information TDFL #1 isrecorded as temporary defect management information TDDS #1 in the firstTDMA.

When recording operation #2 starts, data is recorded in sections {circlearound (5)} through {circle around (7)} and defects #4 and #5 andreplacements #4 and #5 are formed in the user data area A and the sparearea B, respectively, as explained in sections {circle around (1)}through {circle around (4)}. Likewise, the second TDMA is updatedwhenever the verify-after-write method is completed. When recordingoperation #2 is expected to end, the disc drive records informationregarding defects #4 and #5 as temporary defect information TDFL #2 inthe first TDMA and further records information stored in the second TDMAin the first TDMA. Also, management information to manage the temporarydefect information TDFL #2 is recorded as temporary defect managementinformation TDDS #2 in the first TDMA.

FIG. 10 illustrates data structures of temporary defect information TDFL#1 and TDFL #2 according to an embodiment of the present invention. FIG.11 illustrates a data structure of information regarding defect #i.

Referring to FIG. 10, temporary defect information TDFL #1 recorded in afirst TDMA contains information regarding defects #1, #2, and #3. Theinformation regarding defect #1 indicates the position of an area inwhich defect #1 exists and the position of an area in which replacement#1 is recorded. The information regarding defect #2 indicates theposition of an area in which defect #2 exists and the position of anarea in which replacement #2 is recorded. The information regardingdefect #3 indicates the position of an area in which defect #3 existsand the position of an area in which replacement #3 is recorded.

Temporary defect information TDFL #2 recorded in the first TDMA furthercontains information regarding defects #4 and #5 in addition to theinformation recorded in temporary defect information TDFL #1. Morespecifically, temporary defect information TDFL #2 includes theinformation regarding defect #1, the information regarding defect #2,the information regarding defect #3, the information regarding defect#4, and the information regarding defect #5.

Similarly, temporary defect information TDFL #1 recorded in the secondTDMA includes information regarding defect #1. Temporary defectinformation TDFL #2 recorded in the second TDMA includes informationregarding defect #1 and information regarding defect #2. Temporarydefect information TDFL #3 recorded in the second TDMA includesinformation regarding defect #1, information regarding defect #2, andinformation regarding defect #3.

Referring to FIG. 11, information regarding defect #i includes a pointerto defect #i, and a pointer to replacement #i. The pointer to defect #ispecifies starting and ending positions of defect #i. The pointer toreplacement #i specifies starting and ending positions of replacement#i.

A disc defect management method according to an embodiment of thepresent invention will now be described with reference to theaccompanying drawings.

FIG. 12 is a flowchart illustrating a disc defect management methodaccording to an embodiment of the present invention. Referring to FIG.12, when the disc 100 is loaded into the disc drive of FIG. 2, theapparatus reads disc information from a lead-in area and/or a lead-outarea of the disc 100 to determine the type of the disc 100 (action1201). Next, the disc is checked to determine whether the disc 100 is asingle record layer disc or not (action 1202). If the disc 100 isdetermined in action 1202 to be a single record layer disc, a secondTDMA is allocated between a first spare area and a user data area orbetween the user data area and a second spare area, as shown in FIG. 4Aor 4B (action 1203). If the disc 100 is determined in action 1202 to bea double record layer disc, the second TDMA is allocated between thefirst spare area and the user data area and/or between a fourth sparearea and the user data area, as shown in FIG. 7 (action 1204). Next, thedisc drive performs the disc defect management method as describedabove, using a first TDMA and the second TDMA (action 1205).

FIG. 13 is a flowchart illustrating a disc defect management methodaccording to an embodiment of the present invention. Referring to FIG.13, the disc drive of FIG. 2 records user data in a data area of thedisc 100 in units of data to facilitate the verify-after-write method(action 1301). Next, the user data recorded in action 1301 is verifiedto detect an area of the disc having a defect (action 1302). Next, thedisc drive designates the area having the defect as a defective area,rewrites data recorded in the defective area to a spare area so as tocreate a replacement area, and creates pointer information pointing tolocations of the defective area and the replacement area (action 1303).The pointer information is temporarily stored as temporary defectinformation (action 1304) in a first TDMA. Next, a determination is madewhether the verify-after-write method is performed a predeterminednumber of times (action 1305). If the verify-after-write method isperformed the predetermined number of times, the disc drive updates asecond TDMA using the temporarily stored temporary defect information(action 1306). Next, a determination is made whether a recordingoperation is expected to end (action 1307). If the recording operationis expected to end, the disc drive updates the first TDMA and/or thesecond TDMA using the temporarily stored temporary defect information(action 1308). Here, the first TDMA is continuously updated but thesecond TDMA is updated conditionally. For instance, the second TDMA maybe updated whenever the verify-after-write method is completed. Next, adetermination is made whether disc finalization is required or not(action 1309). If disc finalization is required, the information mostrecently updated in the first and second TDMAs is recorded in a DMA(action 1310).

As described above, according to the present invention, a first TDMA anda second TDMA are allocated to a write once disc so that the write oncedisc is compatible with a rewritable disc drive, and disc defectmanagement can be performed on the write once disc using the rewritabledisc drive. For disc finalization, information most recently updated inthe first and second TDMAs is recorded in a DMA, thereby enablinginformation stored in the write once disc to be reproduced by therewritable disc drive.

Although a few embodiments of the present invention have been shown anddescribed, it would be appreciated by those skilled in the art thatchanges may be made in this embodiment without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

1. A method of managing defects in a recording medium, comprising:allocating a first temporary defect management area (TDMA) to a lead-inarea on the recording medium; allocating a second TDMA between thelead-in area and a user data area on the recording medium; reproducingmost recently updated temporary defect information (TDFL) and temporarydefect management information (TDDS) which are recorded on the firstTDMA or the second TDMA, reproducing user data recorded on the user dataarea using the TDFL, wherein the TDFL includes information on a positionof a defective area which occurs within the user data area, and the TDDSincludes information on a recording position of the TDFL.
 2. The methodof claim 1, wherein the recording medium is a write once optical disc.3. The method of claim 1, wherein the recording medium comprises a dataarea comprising a first spare area storing defect replacementinformation, the user data area storing the user data, and a secondspare area storing defect replacement information.
 4. The method ofclaim 3, wherein the second TDMA is recorded in at least one of asection within the data area between the first spare area and the userdata area and a section within the data area between the user data areaand the second spare area.
 5. The method of claim 2, wherein the writeonce optical disc is a dual recording layer optical disc comprising afirst recording layer and a second recording layer.
 6. A method ofreproducing user data in a recording medium, comprising: reproducingmost recently updated temporary defect information (TDFL) and temporarydefect management information (TDDS) which are recorded on a firsttemporary defect management area (TDMA) or a second TDMA of therecording medium; and reproducing user data recorded on a user data areawithin a data area of the recording medium using the TDFL, wherein theTDFL includes information on a position of a defective area which occurswithin the user data area, the TDDS includes information on a recordingposition of the TDFL, the first TDMA is provided in a lead-in area onthe recording medium, and the second TDMA is provided between thelead-in area and the user data area on the recording medium.
 7. A writeonce disc including a lead-in area and a data area, comprising: a firsttemporary defect management area (TDMA) allocated in the lead-in area;and a second TDMA allocated between the lead-in area and a user dataarea within the data area on the recording medium; wherein the firstTDMA or the second TDMA includes temporary defect information (TDFL) andtemporary defect management information (TDDS), and the TDFL includesinformation on a position of a defective area which occurs within theuser data area, and the TDDS includes information on a recordingposition of the TDFL.